%I A070804
%S A070804 0,0,1,1,2,1,3,2,3,2,4,2,5,3,4,4,6,3,7,4,5,4,8,4,8,5,7,5,9,4,10,6,8,6,
%T A070804 9,5,11,7,9,6,12,5,13,8,9,8,14,6,13,8,11,9,15,7,12,9,11,9,16,6,17,10,
%U A070804 11,11,15,8,18,11,14,9,19,9,20,11,12,11,17,9,21,11,16,12,22,9,18,13,16
%N A070804 Number of primes not exceeding phi[n].
%F A070804 a(n)=A000720[A000010(n)]=Pi[phi[n]]
%e A070804 n=50: phi[50]=20,Pi[20]=8=a(50)
%t A070804 Table[PrimePi[EulerPhi[n]], {n, 1, 256}]
%Y A070804 Cf. A007818, A000010, A000720, A070800-A070804.
%Y A070804 Sequence in context: A110917 A070956 A007828 this_sequence A104481 A078709 
               A023022
%Y A070804 Adjacent sequences: A070801 A070802 A070803 this_sequence A070805 A070806 
               A070807
%K A070804 easy,nonn
%O A070804 1,5
%A A070804 Labos E. (labos(AT)ana.sote.hu), May 08 2002